Ball type brake cylinder retainer valve

ABSTRACT

This invention relates to a three-position sealed ball-type brake cylinder pressure retaining valve device, for connection to the exhaust passageway of a railway vehicle brake control valve device. This retaining valve device has a body that is provided at one end with a securing flange. Extending into the body from the other end thereof is a bore that is coaxial with the smaller of a pair of counterbores, the axis of the larger being off-set therefrom. In the larger of these counterbores is disposed a removable cartridge which has formed integral with one end thereof a pair of diametrically arranged arcuate-shaped legs that extend into the smaller counterbore to the end thereof. A pair of diametrically arranged ported resilient arcuate-shaped seal members are disposed in the smaller counterbore between the arcuate-shaped legs and in surrounding sealing relation to a ball-type valve element that has integral therewith a valve stem which extends through the bore in the body for receiving on its outer end a handle manually movable in a plane parallel to the flange selectively to any one of three positions. Extending into the cartridge from its one end is a passageway of small diameter so as to constitute a choke that opens into the smaller of a plurality of coaxial counterbores in one of which is carried an annular valve seat member against which a check valve is normally biased by a spring interposed between the check valve and one end of another of the plurality of counterbores, the check valve thus being arranged in series relation with the choke. The ball-type valve element has therein a plurality of angularly spaced intersecting passageways, one of which is of such size as to constitute a choke, that open at one end at its spherical surface. These passageways of different flow capacity, in cooperation with one another and with either a passageway in the body that at one end opens into the smaller counterbore in this body in alignment with a port in one of the seal members and at the other registers with an arcuate cavity provided in the cartridge and open to the face of the flange via a strainer device, or the check valve, are effective in three respective positions of the ball-type valve element to selectively provide a fast blow-down of brake cylinder pressure to atmosphere, a slow blow-down to a chosen pressure above atmospheric pressure, and a slow blow-down to atmosphere.

United States Patent [191 Scott BALL TYPE BRAKE CYLINDER RETAINER VALVE[75] Inventor: Daniel G. Scott, Apollo, Pa.

[73] Assignee: Westinghouse Air Brake Company, Wilmerding, Pa.

[22] Filed: July 27, 1972 [21] Appl. No.: 275,459

[52] U.S. Cl 137/5992, 137/625.3, 137/625.32, 303/79, 251/363, 251/297[51] Int. Cl F16k ll/lO [58] Field of Search 137/6142, 625.46, 614.14,137/5991, 599.2, 625.29, 625.3, 625.32;

Primary ExaminerSamuel Scott Assistant Examiner-Ira S. Lazarus Attorney,Agent, or FirmRalph W. Mclntire, Jr.; W. F. Poore [57] ABSTRACT Thisinvention relates to a three-position sealed balltype brake cylinderpressure retaining valve device, for connection to the exhaustpassageway of a railway vehicle brake control valve device. Thisretaining valve device has a body that is provided at one end with asecuring flange. Extending into the body from the other end thereof is abore that is coaxial with the smaller of a pair of counterbores, theaxis of the larger being off-set therefrom. In the larger of thesecounterbores is disposed a removable cartridge which has formed integralwith one end thereof a pair of diametrically arranged arcuate-shapedlegs that extend into the smaller counterbore to the end thereof. A pairof diametrically arranged ported resilient arcuate-shaped seal membersare disposed in the smaller counterbore between the arcuate-shaped legsand in surrounding sealing relation to a ball-type valve element thathas integral therewith a valve stem which extends through the bore inthe body for receiving on its outer end a handle manually movable in aplane parallel to the flange selectively to any one of three positions.Extending into the cartridge from its one end is a passageway of smalldiameter so as to constitute a choke that opens into the smaller of aplurality of coaxial counterbores in one of which is carried an annularvalve seat member against which a check valve is normally biased by aspring interposed between the check valve and one end of another of theplurality of counterbores, the check valve thus being arranged in seriesrelation with the choke. The ball-type valve element has therein aplurality of angularly spaced intersecting passageways, one of which isof such size as to constitute a choke, that open at one end at itsspherical surface. These passageways of different flow capacity, incooperation with one another and with either a passageway in the bodythat at one end opens into the smaller counterbore in this body inalignment with a port in one of the seal members and at the otherregisters with an arcuate cavity provided in the cartridge and open tothe face of the flange via a strainer device, or the check valve, areeffective in three respective positions of the ball-type valve elementto selectively provide a fast blow-down of brake cylinder pressure toatmosphere, a slow blow-down to a chosen pressure above atmosphericpressure, and a slow blow-down to atmosphere.

12 Claims, 9 Drawing Figures rat/94,071

PAIENIE FEMSIQM sum 3 or 3 BALL TYPE BRAKE CYLINDER RETAINER VALVEBACKGROUND OF THE INVENTION In U.S. Pat. No. 3,653,406, issued Apr. 4,1972 to Francis R. Racki and assigned to the assignee of the presentapplication, there is shown and described a three-position ball-typebrake cylinder pressure retaining valve device in which the ball-typevalve element has a stepped bottomed bore extending inward from itsspherical surface, in which bore is a spring-biased check valve. Thisvalve element is provided therein with a plurality of angularly spacedpassageways and orifices opening at one end at its spherical surface andat the other either into another passageway also opening at one end atthis spherical surface or into the stepped bottomed bore. It is apparentthat the manufacturing cost of a ball-type retaining valve device inwhich a plurality of passageways and a check valve are embodied in theball valve element is in excess of the cost of such a ball-typeretaining valve device wherein no check valve and a minimum ofpassageways are provided in the ball valve element.

Accordingly, it is the general purpose of this invention to provide animproved, novel, compact, tamperproof three-position ball-type brakecylinder pressure retaining valve device that comprises a ball-typevalve element encased by a pair of ported resilient members forming aseal therewith.

SUMMARY OF THE INVENTION According to the present invention, a novel,tamperproof, three-position brake cylinder pressure retaining valvedevice is provided comprising a valve body that has a bore which iscoaxial with one of a pair of tapered off-set counterbores in thesmaller of which a removable ball-type valve element is encased by apair of diametrically arranged ported resilient arcuate seal members theouter surface thereof abutting the wall surface of the resepctivecounterbore and the inner surface a portion of the spherical surface ofthe valve element. Between each pair of adjacent edges of the two sealmembers, and having a tongue and groove engagement with each respectiveedge, is one of a pair of arcuateshaped legs, the outer surface of whichalso abuts the wall surface of the respective counterbore. These legsare formed integral with one end of an annular cartridge member that isdisposed and retained in the other of the pair of counterbores. Thiscartridge member is provided with a choke and carries a spring-biasedcheck valve so arranged with respect to the choke as to controltherewith serial flow of fluid under pressure therethrough topassageways in the ball valve element that are open to atmosphere viapassageways in the valve body in registry therewith in the differentpositions of the ball valve element. In one position of this valveelement one of the passageways therein, in cooperation with the ports inthe seal members and a pair of the passageways in the valve body,provide for a direct unrestricted flow of fluid under pressure toatmosphere in parallel to the serial flow thereto through the checkvalve and choke.

Integral with the ball-type valve element is a stem that extends throughthe bore in the valve body and receives thereon a handle for manuallyturning the valve element to any one of three different positions so asto selectively provide a fast blow-down of brake cylinder pressure toatmospheric pressure, a slow blow-down of brake cylinder pressure pastthe check valve to a chosen pressure above atmospheric pressurecorresponding to the loading bias on the check valve, and a slow directblow-down of brake cylinder pressure to atmospheric pressure.

In the accompanying drawings:

FIG. l is a front elevational view showing a threeposition brakecylinder pressure retaining valve device constructed in accordance withthe invention.

FIG. 2 is a vertical cross-sectional view, taken along the line 2-2 ofFIG. 1 and looking in the direction of the arrows, showing certainstructural details of this valve device.

FIG. 3 is a vertical cross-sectional view, taken along the line 33 ofFIG. 2 and looking in the direction of the arrows, showing structuraldetails of detent means for retaining the operating handle of theretaining valve device against movement by vibration from any one of itsthree positions.

FIG. 4 is a cross-sectional view, taken along the line 4-4 of FIG. 3 andlooking in the direction of the arrows, showing further structuraldetails of the threeposition brake cylinder pressure retaining valvedevice not made apparent in FIGS. 2 and 3.

FIG. 5 is a partial cross-sectional view, on an enlarged scale, showinga ball valve element of this brake cylinder pressure retaining valvedevice occupying its first position in which an unrestricted and directcommunication is established between a brake cylinder device andatmosphere in parallel relation to a restricted communication having acheck valve disposed therein in series relation thereto.

FIG. 6 is a partial cross-sectional view, on an enlarged scale, with theball valve element shown in the second of its three positions in which achosen pressure is retained in a brake cylinder device.

FIG. 7 is a partial cross-sectional view, on an enlarged scale, with theball valve element shown in the third of its three positions in which arestricted communication is established between a brake cylinder deviceand atmosphere.

FIG. 8 is a top or plan view of one of a pair of arcuate-shaped sealmembers embodied in the brake cylinder pressure retaining valve device.

FIG. 9 is a front elevational view of the arcuateshaped seal memberdisclosed in FIG. 8 showing a pair of tongues or tabs that protrude froma flat surface on the seal member and extend from one end to the otherthereof.

As shown in FIGS. 1 to 7, inclusive, a three-position brake cylinderpressure retaining valve device 1 comprises a casing 2 having therein abore 3 which, as shown in FIGS. 2 and 3, opens at its inner end into acoaxial tapered counterbore 4. As best shown in FIG. 2 of the drawings,the counterbore 4 at its right-hand end opens into a second taperedcounterbore 5 the axis of which is off-set from the axis of thecounterbore 4 bracket (not shown) that is secured to the body of arailway vehicle by any suitable means. This pipe bracket has connectedthereto one end of a brake cylinder exhaust pipe (not shown) that hasits opposite end connected to the exhaust port of the usual fluidpressure operated brake control valve device (not shown) which isprovided on each vehicle in a train. As shown in FIGS. 1, 3 and 4, theflange 6 is provided with two spaced-apart smooth bores 8 for receiving,for example, cap screws (not shown) to secure the flange 6 to the pipebracket.

The above-mentioned one end of the brake cylinder exhaust pipe isdisposed in a bore (not shown) in the pipe bracket which bore is coaxialwith two counterbores 9 and 10 (FIGS. 2 and 3) of unequal diameterformed in the casing 2, it being noted that these counterbores areoff-set the distance X from the counterbore 5 that is connected to thetapered bore 4 in this casing 2 by a passageway 11 also formed in thecasing.

As shown in FIGS. 2, 3 and 4, a spherical or ball-type valve element 12is disposed in the counterbore 4. One

end of this valve element 12 has formed integral therewith a collar 13that abuts the smaller end of the tapered counterbore 4 and a valve stem14 that extends through the bore 3 to the exterior of the casing 2. Thatpart of the valve stem 14 exterior of the casing 2 is provided with asquare portion 15 that extends through a square hole 16 in a handle 17and with a screwthreaded portion 18 that has screw-threaded engagementwith a nut 19 which retains the handle 17 on the square portion 15 ofthe valve stem 14.

As shown in FIGS. 1 and 2, formed integral with the handle 17 andconcentric with the valve stem 14 is an annular member 20 on which iscast or stenciled three arcuately spaced-apart indicia EX, HP and SDdenoting exhaust, high pressure and slow direct positions of the valveelement 12 accordingly as a pointer 21 (FIG. 1) formed on a lug 22 castintegral with the casing 2 overlies EX, HP or SD in response toclockwise turning, as viewed in FIG. 1, of the handle 17. A lug 23formed integral with the annular member 20 abuts a first stop surface 24formed on the right side of lug 22 while the handle 17 occupies itsdirect exhaust position shown in FIG. 1 thereby limiting furthercounterclockwise turning of this handle. A second stop surface 24 formedon the left-hand side of the lug 22 abuts the handle 17 while thepointer 21 overlies SD on member 20 thereby limiting clockwise turningof this handle 17.

As shown in FIGS. 2 and 3, the valve stem 14 is provided with a pair ofspaced-apart peripheral annular grooves in each of which is disposed anO-ring seal 26 that forms a seal with the wall surface of the straightbore 3 to prevent leakage of fluid under pressure from the passageway 11and the interior of counterbore 4 to atmosphere along the periphery ofthe valve stem 14.

As best shown in FIG. 3, a removable annular tapered cartridge member 27that may be constructed of some suitable plastic material is disposed inthe tapered counterbore 5, the axis of which bore, as hereinbeforementioned, is off-set from the axis of the counterbore 4. Formedintegral with the upper end, as viewed in FIG. 3, of the cartridgemember 27 is a pair of frustoconical arcuate-shaped legs 28 and 29.These legs are so tapered and disposed as to extend into the taperedcounterbore 4 and abut the upper end thereof, as shown in FIG. 3. Thearcuate length of the legs 28 and 29 is shown in FIG. 4, it being notedfrom this figure that these legs are diametrically arranged one from theother and that a V-notch 30 is provided at each end of their arcuatelength, this notch extending from one end to the other of the respectiveleg.

The right-hand end, as viewed in FIG. 2, of the cartridge member 27 hasformed integral therewith a flange 31, the center line of this flangebeing off-set the distance X from the center line of the cartridgemember 27 and the diameter being substantially the same as the diameterof the hereinbefore-mentioned counterbore 10 thereby enabling thisflange to be disposed in this counterbore l0 and retained therein by aresilient gasket ring 32 that is disposed in the hereinbeforementionedcounterbore 9 and forms a seal between the flange fitting face 7 on theflange 6 and the abutting corresponding face formed on the pipe bracketwhen the retaining valve device 1 is secured to this pipe bracket by theabove-mentioned cap screws that secure this valve device 1 to the pipebracket.

Extending downward, as viewed in FIG. 3, from the upper end of thecartridge member 27 is a bore 33 of such small diameter as to constitutea choke that opens into a coaxial counterbore 34 that is coaxial with asecond counterbore 35 of larger diameter and a third counterbore 36 thediameter of which exceeds that of the counterbore 35.

Disposed in the counterbore 36 is an annular check valve seat member 37having at its upper end, as viewed in FIG. 3, an annular valve seat 38.This valve seat member 37 is retained in abutting relationship with theshoulder formed by the upper end, as viewed in FIG. 3, of thecounterbore 36 by a snap ring 39 that is inserted in a groove formed inthe wall surface of the counterbore 36.

Disposed in the counterbore 35 is a disc-shaped check valve 40 that isnormally biased against the annular valve seat 38 by a spring 41 whichis interposed between this check valve 40 and a shoulder formed by theupper end of the counterbore 34.

Adjacent its upper end, as viewed in FIG. 3, the cartridge member 27 isprovided with a peripheral annular groove in which is disposed an O-ringseal 42 that forms a seal with the wall surface of the counterbore 5 toprevent leakage therepast of the fluid under pressure that flows to thepassageway 11 while the ball valve element 12 occupies its high pressureposition.

As best shown in FIG. 2, the cartridge member 27 is provided with acavity 270 that registers with one end of the passageway 11 and with thesmaller of a pair of coaxial counterbores 44 and 45 that are provided inthe right-hand end of this member 27, it being noted that the axis ofthese counterbores is off-set the distance X from the axis of thiscartridge member 27.

As shown in FIGS. 2 and 3, a strainer device 46 comprises an annularstrainer member 47 that has substantially the same diameter as thecounterbore 44 and may be constructed of some suitable material such as,for example, felt, and a strainer retaining plate 48 secured thereto bysuch as a rivet 49. It will be understood that the strainer retainingplate 48 is a thin metallic annular member that has a plurality ofradially extending tingers the distance between the tips of twodiametrically oppositely arranged fingers being slightly in excess ofthe diameter of the counterbore 45 whereby those flngers are slightlybent when the strainer device 46 is placed in the assembled positionshown in FIGS. 2 and 3. Accordingly, it will be understood that in theirslightly bent condition the end of each finger exerts a thrust againstthe wall surface of the counterbore to retain the strainer device 46 inthe position in which it is shown in FIGS. 2 and 3.

As best shown in FIG. 4 of the drawings, a pair of identical resilientseal elements 50 are disposed between the two hereinbefore-mentionedlegs 28 and 29. One of these seal elements 50 is shown in detail inFIGS. 8 and 9 of the drawings.

It will be noted from FIGS. 8 and 9 that the seal element 50, which maybe constructed from, for example, rubber, constitutes a segment of afrustrum of a right circular cone. This segment has a flat face 51 fromwhich a spherical sector 52 is removed for receiving in the cavity thusformed a spherical sector having the same size of the ball-type valveelement 12. Furthermore, this segment constituting the seal element 50is provided with a bore 53 that at one end opens into the cavity thatconstitutes the spherical sector 52 and at the other end at the conicaloutside surface on the segment of the frustrum of the right circularcone. It should be noted from FIG. 2 that the location of the bore 53 issuch that in one of the seal elements 50 it is in alignment with theleft-hand end of the passageway l 1 in the casing 2 and in the otherseal element 50 it is in alignment with that end of an outlet passageway54 formed in the casing 2 that opens at the wall surface of the taperedcounterbore 4.

Formed integral with the seal element 50 and extending outward from theflat face 51 thereof and forming a chosen angle therewith are a pair ofspaced-apart tabs 55 and 56, it being noted from FIG. 9 that these tabsextend the entire length of this face 51. The shape, size and locationof these tabs 55 and 56 are such that they fit into the notches 30 inthe frusto-conical arcuateshaped legs 28 and 29 as shown in FIGS. 4 to 7inclusive. It will be further noted from FIGS. 4 to 7 inclusive, thatthe spherical surface provided by the removal of the spherical sector 52from each seal element 50 abuts and forms a seal with the sphericalsurface of the ball valve element 12, and that the surface of each ofthese tabs that does not abut a side of a V-notch 30, and also theinside frusto-conical surface of the arcuate-shaped legs 28 and 29, arespacedv apart from the spherical surface of this ball valve element toform a passageway through which fluid under pressure, after flowing pastthe check valve 40 (FIGS. 2 and 3) and through the choke 33, flows topassageways now to be described in the ball valve element 12.

As shown in FIGS. 2 to 7 inclusive of the drawings, the ball valveelement 12 is provided with a bore or port 57 of large diameter, itbeing noted that the axis of this bore is at a right angle to andslightly off-set from the axis of the valve stem 14 which passes throughthe center of the ball valve element. Consequently, while the valveelement 12 occupies the position shown in FIG. 5, fluid under pressuremay flow from the passageway 11 directly to atmosphere via the bore 53in each of the seal elements 50, the bore 57 in valve element 12, andoutlet passageway 54 which extends through a wall 58 (FIG. 4) that hasformed on its lower side a conical inner surface 59 against which restsa dished circular shield 60.

The shield 60 is preferably formed of a resilient material such asrubber and is held in place by any suitable means such as, for example,a pop rivet which comprises a metallic sleeve 61 that extends throughcoaxial bores in the shield 60 and the wall 58, and a stem 62 having atits upper end a ball-like head. when a pull is exerted on the stem bymeans of a mandrel (not shown), the ball-like head on the upper end ofthe stem acts to flare outward the upper end of the sleeve 61 until thisball-like head becomes encased therein, as shown in FIGS. 2 and 4, itbeing understood that the lower end of the sleeve 61 is concurrentlyflared outward by the mandrel until the opposite ends of the sleeve 61are flared as shown in FIGS. 2 and 4. Subsequent to the flaring of theopposite ends of the sleeve 61 in the manner just explained, thecontinued pull on the stem 62 by the mandrel causes this stem to breakjust below the ball-like head which thereafter maintains the sleeve 61in the position shown in FIGS. 2 and 4. The circumferential surface ofthe shield 60 is adapted to engage the conical surface 59 for preventingaccess to the passageway 54 of particles of foreign matter or by nestbuilding insects such as, for example, mud wasp. It will be noted thatthe surface 59 on the wall 58 extends somewhat beyond the resilientshield 60 so as to provide adequate protection against the formation ofice over the opening in the frusto-conical cavity in the wall 58, andthe shield 60 has sufficient area and flexibility to insure itsdisplacement under the pressure of fluid released from the brakecylinder device to eject any foreign matter that might reach it.

In order to prevent movement of the handle 17 by vibration out of eachof its three positions to which it may be manually moved by a trainman,this handle is provided with three pairs of diametrically arranged andarcuately spaced V-notches or indents 63 and 64, one pair of whichappears in FIG. 3 of the drawings, corresponding to the three positionsof the handle 17. Slidably mounted in each of a pair of diametricallyarranged bottomed bores 65 and 66 provided in the casing 2 is a plunger67 which is yieldingly urged into contact with a corresponding V-notchby a spring 68 interposed between the lower end of the respectiveplunger 67 and the end of the corresponding bottomed bore 65 or 66.

A slow blow-down of brake cylinder pressure to a chosen pressure aboveatmospheric pressure is provided when the ball valve element 12 isrotated to the position shown in FIG. 6. In this position of valveelement 12, fluid under pressure may flow from the brake cylinderthrough the control valve device in its release position, the brakecylinder exhaust pipe, the bore in the pipe bracket to which theretaining valve device 1 is secured, strainer device 46 (FIGS. 2 and 3),annular valve seat member 37, past unseated check valve 40 which isunseated from its seat 38 against the yielding resistance of spring 41by fluid under pressure acting on the lower side (FIG. 3) of this valve410, counterbores 35 and 34, choke 33, the space between the insidefrusto-conical surface of the arcuate-shaped legs 28 and 29 and thespherical surface of the ball valve element 12 (FIG. 6), a large bore orport 69 and a small bore or choke 70 provided in the ball valve element12 each opening at one end into the bore 57 and at the other on thespherical surface of the valve element 12, bore 57, bore 53in the lower(FIG. 6) seal element 50, passageway 54 and past the resilient shield 60(FIGS. 2 and 4) to atmosphere.

In order to provide for a slow direct complete blowdown of fluid underpressure from the brake cylinder, the handle 17 may be turned to itsslow direct position in which the pointer 21 (FIG. 1) overlies theindicium SD on member and the ball valve element 12 occupies theposition shown in FIG. 7. In this position of the ball valve element 12,fluid under pressure may flow from the brake cylinder through the choke33 via the pathway hereinbefore described and thence to atmosphere viathe space between the inside frusto-conical surface of thearcuate-shaped legs 28 and 29 and the spherical surface of the ballvalve element 12 (FIG. 7), bores 57 and 69 in valve element 12, bore 53in the lower (FIG. 7) seal element 50, passageway 54 and past theresilient shield 60 (FIGS. 2 and 3).

Moreover, in this position of the ball valve element 12, fluid underpressure may also flow from the brake cylinder through the strainerdevice 46 via the pathway hereinbefore described and thence toatmosphere via cavity 27a, passageway 11, bore 53 in upper seal element50 (FIG. 7), choke 70, bore 57, bore 53 in lower seal element 50,passageway 54 and past the resilient shield 60.

It will be understood that the usual brake control valve device providedon railway vehicles is operative in the usual manner in effecting abrake release to vent fluid under pressure from the brake cylinder onthe corresponding vehicle by way of the brake cylinder exhaust pipe thathas one end connected to the pipe bracket to which the brake cylinderpressure retaining valve device 1 is secured by cap screws extendingthrough the bores 8 in the flange 7.

This fluid under pressure from the brake cylinder may be releaseddirectly to atmosphere at a fast unrestricted rate, at a slow rate untila chosen pressure above atmospheric pressure is retained in the brakecylinder device, or at a slow rate until the pressure in the brakecylinder device is reduced to atmospheric pressure accordingly as theball valve element 12 is positioned as shown in FIGS. 5, 6 and 7 bymovement to these respective positions by the handle 17.

While the ball valve element 12 occupies its direct release positionshown in FIG. 5, fluid under pressure from the brake cylinder deviceflows through the strainer device 46 (FIG. 2) and thence directly toatmosphere via cavity 27a, passageway 11, bores 53 and 57, passageway 54and past the resilient shield 60 in addition to the flow through thechoke 33 and the pathway hereinbefore described.

While the ball valve element 12 occupies its high pressure positionshown in FIG. 6, fluid under pressure is released from the brakecylinder to atmosphere via the pathway hereinbefore described until achosen pressure, for example, 20 pounds per square inch, dependent uponthe strength of spring 41, is retained in the brake cylinder.

While the valve element 12 occupies its slow direct position shown inFIG. 7, fluid under pressure is completely released from the brakecylinder to atmosphere at a chosen slow rate, dependent upon the size ofthe two chokes 33 and 70, via the two parallel pathways hereinbeforedescribed, it being understood that one of these two chokes is disposedin each of these pathways.

Having now described the invention, what I claim as new and desire tosecure by Letters Patent, is:

I. A brake cylinder pressure retaining valve device comprising:

a. a casing having a bore, a first counterbore, a second counterbore, aninlet port in communication with said second counterbore via which fluidunder pressure from a brake cylinder is admitted to said secondcounterbore, a passageway connecting said first and second counterbores,and an outlet port via which fluid under pressure is released toatmosphere,

b. a removable cartridge member comprising:

i. an element disposed in said second counterbore and having extendingtherethrough a bore of such size as to constitute a choke and aplurality of counterbores, and

ii. a pair of spaced-apart legs integral with said element and sodisposed as to be received in said first counterbore in said casing,

c. a check valve device carried by said element and comprising:

i. a valve seat element disposed in one of said plurality ofcounterbores in said element,

ii. a check valve disposed in another of said plurality of counterboresin said element and interposed between said valves seat element and saidchoke, and

iii. biasing means interposed between said element and said check valvefor normally biasing it in the direction of said valve seat elementwhereby said check valve device and said choke are arranged in seriesrelation,

(1. a pair of seal elements each having a port therein and so disposedin said first counterbore in said casing between said legs that theports therein register respectively with one end of said passageway andwith said outlet port, and

e. a spherical valve element having therein a plurality of ports ofdifferent cross-sectional area certain of which intersect each other,said valve element being disposed in sealing relationship with said sealelements and between said legs in spaced-apart relationship thereto toprovide passageways between said choke in said element and said ports insaid valve element, said valve element having one position in which saidinlet port communicates with said outlet port via a pair of parallelpassageways, one of which includes said check valve device, said choke,said passageways provided between said legs and said valve element, andsaid ports in said valve element, and the other of which includes saidpassageway in said casing, and being rotatable out of said one positionto a first different position in which said inlet port communicates withsaid outlet port only via said one passageway of said pair of parallelpassageways to release fluid under pressure to atmosphere at arestricted rate down to a chosen low pressure determined by the force ofsaid biasing means seating said check valve on said valve seat element,and being rotatable out of said first different position to a seconddifferent position in which said inlet port communicates with saidoutlet port via a second pair of parallel passageways one of whichincludes said one passageway of said first pair of parallel passagewaysand the other of which includes said passageway in said casing and oneof said plurality of ports of different cross-sectional area in saidvalve element, the size of which port constitutes a choke to releasefluid under pressure to atmosphere at a restricted rate.

2. A brake cylinder pressure retaining valve device,

as recited in claim 1, further characterized in that said firstcounterbore in said casing is coaxial with said bore therein, and saidsecond counterbore in said casing is off-set from and tangent to saidfirst counterbore.

3. A brake cylinder pressure retaining valve device, as recited in claim1, further characterized in that said element of said cartridge membercomprises a frustum of a right circular cone.

4. A brake cylinder pressure retaining valve device, as recited in claim1, further characterized in that each of said legs of said cartridgemember has spaced-apart inner and outer surfaces, each surfaceconstituting a portion of the surface of a frustum of a right circularcone.

S. A brake cylinder pressure retaining valve device, as recited in claim1, further characterized in that said element of said cartridge membercomprises a frustum of a right circular cone, and that each of said legsof said cartridge member has spaced-apart inner and outer surfaces, eachsurface constituting a portion of the surface of a frustrum of a rightcircular cone, said legs being integral with one end of said element andso disposed with respect thereto that said outer frustoconical surfacethereon abuts the wall of said first counterbore in said casing.

6. A brake cylinder pressure retaining valve device, as recited in claim1, further characterized in that the axis of said cartridge member anddthe and of rotation of said spherical valve element are parallel, andthe axis of said ports in said spherical valve element lie in a commonplane that is at substantially a right angle to said axes.

7. A brake cylinder pressure retaining valve device, as recited in claim1, further characterized in that each of said seal elements comprises asegment of a frustrum of a right circular cone.

8. A brake cylinder pressure retaining valve device, as recited in claim1, further characterized in that each of said seal elements comprises asegment of a frustrum of a right circular cone having an inner and anouter surface, said inner surface being planar and said outer surfaceconstituting a portion of the surface of said frustrum of a rightcircular cone.

9. A brake cylinder pressure retaining valve device, as recited in claim1, further characterized in that each of said seal elements comprises asegment of a frustrum of a right circular cone having an inner and anouter surface, said inner surface being planar and having formed thereina cavity that constitutes a spherical sector to receive a correspondingspherical sector of said spherical valve element.

10. A brake cylinder pressure retaining valve device, as recited inclaim 1, further characterized by manually operable means for turningsaid spherical valve element from one to another of its positions, andresilient detent means for retaining said manually operable means ineach of said positions against movement therefrom in response tovibration of said retaining valve device.

11. A brake cylinder pressure retaining valve device, as recited inclaim 5, further characterized in that each of said legs has formedtherein between the adjacent opposite ends of said inner and outersurfaces a notch,

and each of said seal elements comprises a segment of a frustrum of aright circular cone having an inner planar surface and a pair ofspaced-apart tabs extending from said surface, said tabs being sodisposed that one is received in one of the notches in one of said pairof legs and the other is received in one of the notches in the otherleg.

12. A brake cylinder pressure retaining valve device, as recited inclaim 9, further characterized in that the axis of said spherical sectorconstituting the cavity in each of said seal elements coincides with theaxis of said port therein which port extends from said outer surface tosaid cavity.

Egg? UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Plum: 3,79 h7 Dated February 26, 1971;

rnvmom DenielG. Scott It is certified that error appears in theabove-identified patent end that aid Letters Patent are hereby correctedas shown below:

Column 8, line 20, "valves" should be --valve-- Y 1 Column 9, I

line 26,- i'andd, first occurrence, should be --a.nd--

line26, "and", second occurrence, should be Signed and sealed this 24thday of September 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. c. MARSHALL DANN Attesting Officer CommissionerofPatents

1. A brake cylinder pressure retaining valve device comprising: a. acasing having a bore, a first counterbore, a second counterbore, aninlet port in communication with said second counterbore via which fluidunder pressure from a brake cylinder is admitted to said secondcounterbore, a passageway connecting said first and second counterbores,and an outlet port via which fluid under pressure is released toatmosphere, b. a removable cartridge member comprising: i. an elementdisposed in said second counterbore and having extending therethrough abore of such size as to constitute a choke and a plurality ofcounterbores, and ii. a pair of spaced-apart legs integral with saidelement and so disposed as to be received in said first Counterbore insaid casing, c. a check valve device carried by said element andcomprising: i. a valve seat element disposed in one of said plurality ofcounterbores in said element, ii. a check valve disposed in another ofsaid plurality of counterbores in said element and interposed betweensaid valves seat element and said choke, and iii. biasing meansinterposed between said element and said check valve for normallybiasing it in the direction of said valve seat element whereby saidcheck valve device and said choke are arranged in series relation, d. apair of seal elements each having a port therein and so disposed in saidfirst counterbore in said casing between said legs that the portstherein register respectively with one end of said passageway and withsaid outlet port, and e. a spherical valve element having therein aplurality of ports of different cross-sectional area certain of whichintersect each other, said valve element being disposed in sealingrelationship with said seal elements and between said legs inspaced-apart relationship thereto to provide passageways between saidchoke in said element and said ports in said valve element, said valveelement having one position in which said inlet port communicates withsaid outlet port via a pair of parallel passageways, one of whichincludes said check valve device, said choke, said passageways providedbetween said legs and said valve element, and said ports in said valveelement, and the other of which includes said passageway in said casing,and being rotatable out of said one position to a first differentposition in which said inlet port communicates with said outlet portonly via said one passageway of said pair of parallel passageways torelease fluid under pressure to atmosphere at a restricted rate down toa chosen low pressure determined by the force of said biasing meansseating said check valve on said valve seat element, and being rotatableout of said first different position to a second different position inwhich said inlet port communicates with said outlet port via a secondpair of parallel passageways one of which includes said one passagewayof said first pair of parallel passageways and the other of whichincludes said passageway in said casing and one of said plurality ofports of different cross-sectional area in said valve element, the sizeof which port constitutes a choke to release fluid under pressure toatmosphere at a restricted rate.
 2. A brake cylinder pressure retainingvalve device, as recited in claim 1, further characterized in that saidfirst counterbore in said casing is coaxial with said bore therein, andsaid second counterbore in said casing is off-set from and tangent tosaid first counterbore.
 3. A brake cylinder pressure retaining valvedevice, as recited in claim 1, further characterized in that saidelement of said cartridge member comprises a frustum of a right circularcone.
 4. A brake cylinder pressure retaining valve device, as recited inclaim 1, further characterized in that each of said legs of saidcartridge member has spaced-apart inner and outer surfaces, each surfaceconstituting a portion of the surface of a frustum of a right circularcone.
 5. A brake cylinder pressure retaining valve device, as recited inclaim 1, further characterized in that said element of said cartridgemember comprises a frustum of a right circular cone, and that each ofsaid legs of said cartridge member has spaced-apart inner and outersurfaces, each surface constituting a portion of the surface of afrustrum of a right circular cone, said legs being integral with one endof said element and so disposed with respect thereto that said outerfrusto-conical surface thereon abuts the wall of said first counterborein said casing.
 6. A brake cylinder pressure retaining valve device, asrecited in claim 1, further characterized in that the axis of saidcartridge member andd the and of rotation of said spherical valveelement are parallel, And the axis of said ports in said spherical valveelement lie in a common plane that is at substantially a right angle tosaid axes.
 7. A brake cylinder pressure retaining valve device, asrecited in claim 1, further characterized in that each of said sealelements comprises a segment of a frustrum of a right circular cone. 8.A brake cylinder pressure retaining valve device, as recited in claim 1,further characterized in that each of said seal elements comprises asegment of a frustrum of a right circular cone having an inner and anouter surface, said inner surface being planar and said outer surfaceconstituting a portion of the surface of said frustrum of a rightcircular cone.
 9. A brake cylinder pressure retaining valve device, asrecited in claim 1, further characterized in that each of said sealelements comprises a segment of a frustrum of a right circular conehaving an inner and an outer surface, said inner surface being planarand having formed therein a cavity that constitutes a spherical sectorto receive a corresponding spherical sector of said spherical valveelement.
 10. A brake cylinder pressure retaining valve device, asrecited in claim 1, further characterized by manually operable means forturning said spherical valve element from one to another of itspositions, and resilient detent means for retaining said manuallyoperable means in each of said positions against movement therefrom inresponse to vibration of said retaining valve device.
 11. A brakecylinder pressure retaining valve device, as recited in claim 5, furthercharacterized in that each of said legs has formed therein between theadjacent opposite ends of said inner and outer surfaces a notch, andeach of said seal elements comprises a segment of a frustrum of a rightcircular cone having an inner planar surface and a pair of spaced-aparttabs extending from said surface, said tabs being so disposed that oneis received in one of the notches in one of said pair of legs and theother is received in one of the notches in the other leg.
 12. A brakecylinder pressure retaining valve device, as recited in claim 9, furthercharacterized in that the axis of said spherical sector constituting thecavity in each of said seal elements coincides with the axis of saidport therein which port extends from said outer surface to said cavity.